<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>

    <style>
        div {
            display: flex;
            /* flex-direction: column; */
            width: 800px;
            height: 400px;
            background-color: pink;
            /* 默认主轴为x轴 row */
            /* 设置主轴居中 */
            justify-content: center;
            /* 设置侧轴居中 */
            align-items: center;
        }

        span {
            width: 150px;
            height: 100px;
            background-color: skyblue;
            color: #fff;
            margin: 10px;
        }
    </style>

</head>
<body>
    <img src="../flex-设置侧轴排列方式.png" alt="">
    <br>
    <img src="../flex-设置侧轴排列属性.png" alt="">

    <div>
        <span>1</span>
        <span>2</span>
        <span>3</span>
    </div>

</body>
</html>